Wait, you first wait 3 ticks and then assign the me to Titel_ent. But the nouncers() action gets already loaded and makes use of Titel_ent before you assigned it. Since you only declared an empty pointer (without the = NULL at definition) it will result in a crash.

I always declare my variables with a default value, e.g. ENTITY* Titel_ent = NULL; to prevent crashes. And you should build in a while (Titel_ent == NULL) {wait(1);} check too in nouncers().